Muscle's

Shoulder girdle

Trapezius

Origin

Back of the skull


Insertion

Spine of scapula and lateral edge of clavicle


Joint Actions

Upper fibres elevate the shoulder girdle

Middle fibres retract shoulder girdle

Lower fibres depress shoulder girdle

Rhomboids

Origin

Spinous process of cervical and thoracic vertebrae


Insertion

Medial border of scapula


Joint actions

Retracts scapula

Downwardly rotates scapula

Levator Scapulae

Origin

Transverse processes of cervical vertebrae


Insertion

Medial border of scapula, between superior angle and root of the spine


Joint action

Origin fixed: Elevates the scapular. Assists in downwards rotation of scapula

Insertion fixed: Laterally flexes the next

Serratus Anterior

Origin

Front of ribs 1-8


Insertion

Anterior surface of medial border of scapula


Joint Action

Protracts the scapula

Upwardly rotates scapula

Pectoralis Minor

Origin

Front of ribs


Insertion

Coracoid process of scapula


Joint action

Origin fixed: Protracts the scapula. Downwardly rotates scapula.

Insertion fixed: Elevates ribs during breathing

Scapula and Clavicle - Shoulder Girdle - Anatomy Tutorial
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